Islamabad , Pakistan -LRB- CNN -RRB- -- Intense rains let up in parts of northwestern Pakistan on Thursday , giving humanitarian groups a chance to get more aid to the millions of people suffering .

The dry skies were a respite for areas battered by the heavy rains , which left behind bloated rivers and covered whole neighborhoods with flood waters .

But heavy rains were still pounding some parts of the country , including Punjab and Sindh provinces .

The flooding -- caused by torrential monsoon rains -- has destroyed thousand of homes , crushed many bridges and affected 3 million people , officials said .

As many as 1,500 people have died in what has been called Pakistan 's worst flooding in 70 years .

`` Today is going better . It is sunny and drier , but the destruction is all around us . Most of the villages have been washed away by water , '' said Joseph Prior Tio , who 's working with Doctors Without Borders in Pakistan 's Swat Valley .

Another big issue is the many left without electricity , Tio said .

`` We are fighting to get safe water to many areas , '' Tio said `` There is simply no electricity anywhere in the entire valley . All over the valley there are about 1 million people who depended on electricity to get basic services such as safe drinking water . ''

U.S. Secretary of State Hillary Clinton on Wednesday urged Americans to donate to relief efforts , saying that experience in post-earthquake Haiti showed that small donations can make a big difference .

Pakistani Prime Minister Yousuf Raza Gilani appealed to residents to curtail expenditures for Ramadan feasts and upcoming independence day celebrations , and instead help their suffering compatriots .

@highlight

Rain lets up in some areas of flood-hit Pakistan

@highlight

Secretary of State Hillary Clinton appeals for aid

@highlight

About 3 million people have been affected by monsoon rains and flooding